Testing three explanations of the emergence of weapon carrying in peer context: the roles of aggression, victimization, and the social network.

PURPOSE To examine the relative contribution of weapon carrying of peers, aggression, and victimization to weapon carrying of male and female adolescents over time. METHODS Data were derived from a population-based sample of male (N = 224) and female (N = 244) adolescents followed from grade 10 (M age = 15.5) to grade 11 (M age = 16.5). Peer networks were derived from best friend nominations. Self-reports were used to assess weapon carrying. Aggression and victimization were assessed using both self- and peer-reports. Use of dynamic social network modeling (SIENA) allowed prediction of weapon carrying in grade 11 as a function of weapon carrying of befriended peers, aggression, and victimization in grade 10, while selection processes and structural network effects (reciprocity and transitivity) were controlled for. RESULTS Peer influence processes accounted for changes in weapon carrying over time. Self-reported victimization decreased weapon carrying 1 year later. Peer-reported victimization increased the likelihood of weapon carrying, particularly for highly aggressive adolescents. Boys were more likely to carry weapons than girls, but the processes associated with weapon carrying did not differ for boys and girls. CONCLUSIONS These findings revealed that, in this population-based sample, weapon carrying of best friends, as well as aggression, contributed to the proliferation of weapons in friendship networks, suggesting processes of peer contagion as well as individual vulnerability to weapon carrying.